Originally Posted by: renA friend of mine has an old acoustic with a neck like a boomerang that he keeps in the corner as a visual aid for anyone who doubts it... ;)

I have Yamaha C 40, and once I've changed my nylon strings to metal strings (heavy gauge). I was scared when I weared them on - I felt that the tension is too high. So I've thrown new strings away to keep my guitar alive :)

imo, every player has to choose gauge for himself (herself). But just before that find out if your guitar is able to get over it.